Sewing-machine.



M. T. DENNE.

SEWING MACHINE.

APPLICATION FILED SEPT. 22. 1914.

Patented Apr. 10, 1917.

Mark Thomas Dn ne,

7M Slaw W Atty's.

SEWING-MACHINE.

Specification of Letters Patent.

Patented Apr. 10, 191%.

Application filed September 22, 1914. Serial No. 863,020.

To all whom it may concern:

Be it known that I, MARK THOMAS DENNE, a subject of the King of Great Britain and Ireland, residing at Rushden, Northamptonshire, England, have invented new and useful Improvements in and Relating to Sewing-Machines, of Which the following is a specification.

This invention has reference to improvements in and relating to sewing machines of the type having acurved needle and a curved awl which oscillate around different axes, and the main objects of my invention are to simplify the construction of such machines, more especially welt sewing machines, and to actuate the needle and awl by such a direct thrust that the mechanism 'whereby movement is imparted from the usual cam shaft to the said needle and awl may be made much lighter than heretofore.

To this end my invention comprises inter (did, means for use in a sewing machine in which a curved needle and a curved awl are employed, whereby, whether the needle and awl oscillate through the same or through different angles of movement, the oscillations of both the needle and awl are derived from a single cam or equivalent such as an eccentric or crank pin. Further, if desired, the presser foot or channel guide may also have its required movements imparted to it from the said cam or equivalent.

I have illustrated one embodiment of my invention in the accompanying drawing, in

which Figures 1 and 2 are aside and front elevation respectively of means for imparting movement to the needle, and

Figs. 3 and 4: are a side and front elevation respectively of -means for imparting movement to the awl and the presser foot or channel guide in accordance with the invention.

Referring to the drawing, the numeral 1 indicates the usual cam shaft and 2 is a shaft or spindle mounted on the frame of the machine a suitable distance from and parallel to the said cam shaft. 011 the said spindle and in the plane in which the needle.

oscillates I fixedly mount a lever 3 the free end of which is pivotally connected to a link l which in turn is pivotally connected to the needle carrying segment 5 so that by rocking the spindle 2 through a suitable angle the needle will be caused to oscillate through its required angle of movement. In Fig. 1 the needle 6 is shown in the position it occupies at the end of its stroke after passing through the work, and when in this position it will be seen that the centers of the pivots at the ends of the link 4 and the center of the spindle 2 are in alinement. The relative lengths of the lever 3 and link 4 and the distance fromthe center of oscillationof the needle to the point at which the link 1 is connected to the needle carrying segment 5 are such that the link 1 will be at all times substantially tangential to the circle described by the said point as the segment oscillates. There is consequently such a direct thrust brought to bear that the said lever and link may be made very light even when the machine is built for heavy work.

The cam or equivalent from which movement is to be imparted from the cam shaft 1 to the lever 3 is also arranged in 'the plane .in which the needle oscillates. I have shown in the drawings the simplest form of equivalent of a cam, viz. a crank pin carried by disks 8 fixed on the shaft 1. A- jointed connecting rod 9, 9 is mounted on the crank pin and connected at its other end to the lever 3 by a pin 10 and rectangular block l0 mounted rotatably on the said pin and slidable in atransverse slot 91 formed in-the rod or bar 9. The said rod or bar 9 is carried in a fixed bearing (not shown) through which it slides or reciprocates axially, its axis being preferably radial to the cam shaft 1 as shown in the drawing.

Closely adjacent to the needle operating lever 3 I mount a second lever 11 on the spindle 2 to operate the awl 12', which awl operating lever 11 has a boss or hearing to receive the pivot pin of a short link 13 the other end of which link is pivotally connected to a segmental rocking plate 14: (to which the awl is secured) preferably by being made cylindrical to fit snugly in a correspondingly shaped recess in the said segmental rocklng plate. This plate 14: is pivotally supported at on a plate 16 that is bolted to, the feed slide 17. The arrangement and dimensions of the lever 11 and I link 13 and the distance from the center of oscillation of the rocking plate 14 to the point at which the said link is connected thereto are such that the link will be at all times substantially tangential to the circle described by the said point as the plate oscillates.

Although both the needle 6 and the awl 12 derive their movement from the cam shaft 1 through 7 one and the same reciprocating member 9, the awl by the arrangement or means described may be made to oscillate through a less angle than the needle and I prefer when for example my invention is applied to welt sewing machines, in which the awl is only required to feed the work that the awl oscillates through a less angle than the needle, so that in leaving the work the point of the awl will not contact with the insole at a point outside the hole made by the needle and thus score or mark the work. This arrangement is shown clearly in Fig. 3 of the drawing in which 15 indicates the axis around which the awl oscillates and 6 the axis around which the needle oscillates. The point at which the paths of the needle and awl intersect each other is indicated by the numeral 18.

The channel guide or presser foot 19 is carried on a block 20 which is pivotally mounted on the same stud 15 on which the awl carrying rocking plate 14 is mounted. Said block has a part extending as an arm on-the end of which I mount an anti-friction roller 21 and the awl actuating lever 11 is formed or provided with an arc-shaped extension 22 which engages the roller 21. The

' arc-shaped extension has a part 61preferably at its end-formed or cut away as a cam or equivalent,.the arrangement being such that. when the'awl is in the Work and is feeding the latter along, the presser foot or channel guide 19 will be slightly raised.

The mechanism whereby movement is imparted tothe needle and awl and also to the presser foot or channel guide being located practically directly over these members and in their plane of. movement, and thethrust rod ,9 whereby rocking movements are imparted to thespindle carrying the levers 3 and 11 acting substantially in the plane of movement of thesaid members, the sa1d mechanism may be made much lighter in the cam cylinder can be made shorter and therefore lighter than whenseveral cams are required. 7 i

Asa result, not only 1s the cost of the cam cylinder reduced but owing to the considerable reduction in weight of the needle and awl actuating mechanism due to the direct application of the actuating force, the machine can be run at a much higher speed than those heretofore known as high speed machines and, further, owing to the reduction in weight of the rapidly moving mechanism the practically instantaneous starting and stopping at their highest speed of all the parts entails much less strain and less loss of power than is the case with machines in which the corresponding parts must be made comparatively heavy owing to the power being transferred or transmitted more or less indirectly.

WVhat I'claim as my invention and desire to secure by Letters Patent is 1. I11 a sewing machine, the combination with a curved needle and its needle-carrying segment, of a curved awl and its awl-carrying segment, means for supporting said segments for oscillatory movement about different axes, an actuating cam, and connections between said cam and both of said segments by which oscillatory movement is given to each segment from said cam.

2. In a sewing machine, the combination with a curved needle and its needle-carrying segment, of a curved awl and its awl-carrying segment, means for supporting said segments for oscillatory movement about different axes, a cam, a connection between said cam and the needle-carrying segment by which the latter is given its oscillatory movement, a second connection between said cam and the awl-carrying segment by which it is given an oscillatory movement through a smaller angle than the oscillatory movement of the needle-carrying segment.

3. In a sewing machine, the combination with a curved needle and its needle-carrying segment, of a curved awl and its awl-carrying segment, means for supporting said segments for oscillatory movement about different axes, a common actuating member for both segments, an operative connection between said actuating member and each segment, which includes links pivoted to the segments and extending substantially tangential to the arc of movement of the segments.

4:; In a sewing machine, the combination with a curved needle and its needle-carrying segment, of a curved awl and its awl-carrying segment, means for supporting sa1d segments for oscillatory movement, a presserfoot supported to turn about the axis of movement of the awl-carrying segment, an actuating member, connections between said member and each of said segments, the connection to the awl-carrying segment having means to oscillate the presser-foot.

5. In a sewing machine, the combination with a curved and and its avvl-cairrying segment, of means to sustain said avvl for oscillating movement, a pressenfoot mounted for turning movement about the axis of movement of the aWl-carrying segment, actuating means for the aWl-carrying segment comprising a lever and a link connecting said lever With said segment, said lever having an extension, and means by Which said extension operates the presser-foot to release 10 the Work as it is fed by the and.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

MARK THOMAS DENNE.

Witnesses:

A. E. WILLIAMS, M. POTTON,

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. O. 

